STMICROELECTRONICS L3037

L3037
SUBSCRIBER LINE INTERFACE CIRCUIT
MONOCHIP SILICON SLIC SUITABLE FOR
PUBLIC/PRIVATE APPLICATIONS
IMPLEMENTS ALL KEY FEATURES OF THE
BORSCHT FUNCTION
SOFT BATTERY REVERSAL WITH PROGRAMMABLE TRANSITION TIME (3 to 100ms)
METERING PULSE INJECTION AND FILTERING WITH MINIMAL COMPONENTS COUNT
(NO TRIMMING REQUIRED).
PROTECTION RESISTOR MISMATCH COMPENSATION
ON HOOK TRANSMISSION
LOOP START/GROUND START FEATURE
IND TEMP. RANGE:
-40°C TO +85°C
LOW POWER DISSIPATION IN ALL OPERATING MODES
INTEGRATED ZERO CROSSING RELAY
DRIVER
INTEGRATED (NOISE-LESS) RING TRIP DETECTION
VERY LOW NO. of STD TOLERANCE EXTERNAL COMPONENTS
SELECT PART FOR U.S. APPLICATIONS
(63dB TYP. LONG. BALANCE)
SURFACE MOUNT PACKAGE (PLCC44 or
BLOCK DIAGRAM
December 1997
PLCC44
PQFP44(10 x 10)
ORDERING NUMBERS:
L3037FN
L3037QN
PQFP44)
INTEGRATED THERMAL PROTECTION
PIN TO PIN COMPATIBLE WITH L3035/36
DESCRIPTION
The L3037 subscriber line interface circuit is a bipolar device in 70V technology developed for central office / loop carrier and private applications.
The L3037 is pin to pin and function compatible
with L3035/36. One particular pin (reserved in
L3035/36) is now used for reverse polarity transition time programming. The line polarity transition
is not affecting the AC signal transmission that
can continue also during the line voltage transition.L3037 is available in two different package
options: PLCC44 and PQFP44 (10 x 10mm).
1/22
This is advanced information on a new product now in development or undergoing evaluation. Details are subject to change without notice.
L3037
L3037 PIN FUNCTIONALITY (PLCC44)
No.
1
2
3
4
5
6
7
8
9
10 to14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32 to 36
37
38
39
40
41
42
43
44
Name
VCC
ILTF
RDC
CF
BASE
BGND
VREG
STIP
TIP
VB
RING
SRING
CRT
ODET
RGIN
OGK
GST
D1
D0
LIM
VSS
REL
CREV
GREL
CAC
RS
ZB
VB
Tx
Rx
ZAC
TTXIN
RTTX
ACFD
AGND
IREF
Function
Supply input (+5V)
Analog output (current source)
Analog input (current input)
Analog input (voltage input)
Analog output (voltage source)
Ground input (0V)
Supply input (VREG)
Analog input (voltage input)
Analog output (voltage output)
Supply input (-VBAT)
Analog output (voltage output)
Analog input (voltage input)
Analog input/output (voltage input / current output)
Digital output (voltage output with internal pull up)
Analog input (current input)
Digital output (voltage output with internal pull up)
Digital input (voltage input, internal pull down)
Digital input (voltage input)
Digital input (voltage input)
Digital input (voltage input 3 levels: 0, +5, open)
Supply input (-5V)
Digital output (voltage output open drain)
Analog input/output (voltage input/current output)
Ground input (0V)
Analog input (current input)
Analog input/output (current output/voltage input)
Analog input (voltage input)
Supply input (-VBAT)
Analog output (voltage output)
Analog input (voltage input)
Analog output (voltage output)
Analog input (voltage input)
Analog output (voltage output)
Analog input (voltage input)
Ground input (0V)
Analog input/output (voltage output/current input)
L3037 FUNCTIONAL DIAGRAM
GREL
REL
CRT
OGK
RGIN
STIP
ICRT
ODET
ILT
(IA+IB)/200
ILL
(IA-IB)/200
IA
1
TIP
D0
LOGIC
INTERFACE
&
DECODER
D1
GST
LIM
LINE
STATUS
ILT
VREF
ICRT
0 CROSS
DETECT.
IB
-1
RING
SRING
LINE
INTERFACE
SUPERVISION
COMMANDS
(IA+IB)/200
AC+DC
AC
BGND
DC
TTXIN
RX
VREG
ILTF
BIAS
2.32
1
ZAC
1
REFERENCE
&
BIAS
SWITCHING
ZB
TX
D94TL136
2/22
1+
AC
PROCESSOR
ACFD
RS
DC
PROCESSOR
IREV
CAC
RTTX
IREF
VCC
VSS
AGND
CREV
VB
RDC
SUPPLY
REGULATOR
CF
BASE
L3037
AGND
N.C.
ACFD
RTTX
41
IREF
RDC
42
ILTF
CF
43
VCC
BASE
44
40
39
38
37
36
35
34
VB
1
33
TTXIN
VREG
2
32
ZAC
STIP
3
31
RX
TIP
4
30
TX
N.C.
5
29
N.C.
N.C.
6
28
VB
N.C.
7
27
N.C.
RING
8
26
N.C.
SRING
9
25
ZB
N.C.
10
24
RS
CRT
11
23
CAC
12
13
14
15
16
17
18
19
20
21
22
RGIN
OGK
GST
D1
D0
LIM
VSS
REL
CREV
GREL
PQFP44
ODET
PLCC44
BGND
PIN CONNECTION (Top view)
D94TL129
ABSOLUTE MAXIMUM RATINGS
Symbol
Vbat
VCC
VSS
Vag nd Vbgnd
VREL
Vdig
Idig
Tj
Tstg
Hu
Parameter
Battery Voltage
Positive Supply Voltage (0 to 1ms)
(continuous)
Negative Supply Voltage (0 to 1ms)
(continuous)
Agnd Respect Bgnd (continuous)
Ring Relay Supply Voltage
Digital I/O D0, D1, GST, LIM, ODET, OGK
Digital I/O D0, D1, GST, LIM, ODET, OGK
Maximum Junction Temperature
Storage Temperature
Humidity
Value
-64 to VSS+0.5
-0.4 to +7
-0.4 to +5.5
-7 to +0.4
-5.5 to +0.4
-2 to +2
Unit
V
V
V
V
V
V
14
-0.4 to +5.5
-3 to +3
+150
-55 to +150
5 to 95
V
V
mA
°C
°C
%
Note: In case of power on, power failure or hot insertion with V DD, VSS present and Vbat floating the Absolute Maximum Ratings can be exceeded
with Vbat > VSS +0.5V. In this case the power consumption of the device increases and the logic output state including relay driver are
not controlled. This effect can be prevented ensuring that Vbat is always present before V DD and VSS or connecting one shottky diode
(e.g. BAT49X or equivalent) between Vbat and VSS. One diode can be shared between all the SLICs of the same line card.
OPERATING RANGE
Symbol
Top
Vag nd Vbgnd
VCC
VSS
Vbat
VREL
Parameter
Operating Temperature Range
Difference between Agnd and Bgnd
Positive Supply voltage
Negative Supply Voltage
Battery Voltage
Ring Relay Supply Voltage
Value
-40 to +85
-2 to +2
Unit
°C
V
+4.5 to +5.5
-5.5 to -4.5
-62 to -17
4 to 13
V
V
V
V
THERMAL DATA
Symbol
Rth j-amb
Parameter
Thermal Resistance Junction-ambient
Max.
PLCC44
PQFP44
Unit
45
75
°C/W
3/22
L3037
PIN DESCRIPTION
Unless otherwise specified all the diagrams in this datasheet refers to the PLCC44 Pin Connection.
PQFP44
No.
PLCC44
No.
Pin
Description
39
1
VCC
Positive Power Supply (+5V)
40
2
ILTF
Transversal Line Current Image ((IA + IB) / 200)
41
3
RDC
42
4
CF
43
5
BASE
Driver for external transistor base
44
6
BGND
Battery ground
2
7
VREG
Regulated Voltage. Provides negative power supply for the power amplifier.
(connected to emitter of the external transistor.)
3
8
STIP
4
9
TIP
A line termination output (IA is the current sourced from this pin).
1, 28
10 to 14
32 to 36
VB
Battery Supply
PLCC44: All pins are internally connected together.
PQFP44: It is mandatory to short pin 1 and pin 28 as closed as possible to the device.
8
15
RING
9
16
SRING
11
17
CRT
12
18
ODET
ON/OFF hook and RING TRIP output (when disable is internally pulled up)
13
19
RGIN
Ring input signal. (when open is internally pulled to GND)
14
20
OGK
Ground key output (when disable is internally pulled up)
15
21
GST
16
22
D1
Bit 1
17
23
D0
Bit 0
18
24
LIM
Current Limitation Program. (when open is internally forced to 44mA current limitation)
19
25
VSS
Negative Power Supply (-5V)
20
26
REL
Ring relay driver output
21
27
CREV
22
28
GREL
23
29
CAC
AC feedback input (ACDC split capacitor is connected from this node to ILTF)
24
30
RS
Protection resistors image (the image resistor is connected from this node to ACFD)
25
31
ZB
Balance network for 2 to 4 wire conversion (the balance impedance ZB is connecetd
from this node to AGND. The ZA impedance is connected from this node to ZAC)
30
37
Tx
4 wire output port (Tx output)
31
38
Rx
4 wire receiving port. (Rx input)
Rx buffer output (the AC impedance is connected from this node to ACFD)
Input of A power amplifier (when no compensation of ext. ptc resistor mismatch is
requested it must be shorted to the TIP lead).
B line termination output (IB is the current sunk into this pin).
Input of B power amplifier (when no compensation of ext. ptc resistor mismatch is
requested it must be shorted to the RING lead).
Ring trip and ground key capacitor
A open command (when open is internally pulled down)
Reverse polarity transition time control. One proper capacitor connected between this
pin and AGND is setting the reverse polarity transition time. If reverse polarity feature
is not used must be open or connected to AGND through a filter capacitor.
Ground reference for ring relay driver
32
39
ZAC
33
40
TTXIN
Metering input port/Vdrop programming. If not used should be connected to AGND.
34
41
RTTX
Metering cancellation network. If not used should be left open.
35
42
ACFD
AC impedance synthesis
37
43
AGND
DC and AC signal ground
38
44
IREF
Voltage Reference Output
N.C.
Not connected
2,5 to 7,
10,26,
27, 29,36
4/22
DC feedback input (the RDC resistor is connected from this node to ILTF)
Battery voltage ripple rejection (CSVR capacitor is connected from this node to BGND).
–
L3037
DESCRIPTION (continued)
One special selection with high longitudinal balance performances allows to meet the United States
BELLCORE requirements for central office/loop
carrier and private applications.
The SLIC integrates loop start, ground start,
ground key on/off-hook, automatic ring-trip as well
as zero crossing ring relay driver.
Two to four wire conversion is implemented by the
SLIC for application with first generation COMBO.
In case of application with second generation (programmable) COMBO this function can be implemented outside saving external components.
The L3037 offers programmable current limitation
(3 ranges), on hook transmission and low power
in all operating modes, power management is
controlled by a simple external low cost transistor.
Metering pulses are injected on the line via a summing node through TTXIN pin.
Metering pulse filtering is performed by means of a
simple RC network with standard tolerance components. In case TTX function is not used this pin
must be connected to AGND. It is also possible to
use this pin to modify the DC voltage drop between
TIP/RING terminals and battery voltage for appications where it is important to optimize the battery
voltage supply versus the signal swing.
Effect of protection resistors mismatch are compensated by a feedback loop on the final stage allowing good long balance performances also with
large tolerance protection resistors (ex: PTC).
This function allow the L3037 to be fully conform
to BELLCORE power cross and surge test and
meet also the Longitudinal Balance Specification
without using matched PTC resistors.
An integrated thermal protection circuit forces the
L3037 in POWER DOWN (PD) mode when the
junction temperature exceeds 150°C Typ.
The L3037 is specified over -40°C to +85°C ambient temperature range.
The L3037 package is a surface mount PLCC44
or PQFP44.
FUNCTIONAL DESCRIPTION
L3037 is designed in 70V bipolar technology and
performs the telephone line interface functions required in both C.O. and PABX environments. The
full range of signal transmission, battery feed,
loop supervision are performed.
Signal transmission performance is compatible
with European and North American Standards
and with CCITT recommendations.
Ringing, overvoltage and power cross protection
are performed by means of external networks.
The signal transmission function includes both 2
to 4 wire and 4 to 2 wire conversion. The 2W termination impedance is set by means of an external impedance which may be complex. The 2 to 4
wire conversion is provided by means of an external network.
Such a network can be avoided in case of applications with COMBOII, in this case the 2 to 4 wire
conversion is implemented inside the COMBOII
by means of the programmable Hybal filter.
An additional input allows a metering pulse signal
to be added on the line.
The DC feed resistance is programmable with
one external resistor. Three different values of
current limitation (25, 44, 55mA)can be selected
by software through the parallel digital interface.
One external transistor reduces the power dissipation inside the L3037 in the presence of a short
loop (limiting current region).
An additional supervisory function sets the TIP
lead into high impedance state in order to allow
application in ground start configurations.
The different L3037 operating modes are controlled by a 4bit logic interface, two additional detector outputs provide ground key detection and either hook state or ring trip detection.
SLIC OPERATING MODES
Through the L3037 digital interface it is possible
to select 5 different SLIC operating modes:
1) Active Mode (ACT)
2) Standby Mode (SBY)
3) Tip Open Mode (TO)
4) Power Down Mode (PD)
5) Ringing Mode (RNG)
In both ACT and SBY modes it is possible to select the reverse polarity (see control interface).
Transition from direct to reverse polarity is soft
and the transition time is defined by the external
capacitor CREV.
ACTIVE MODE (ACT)
This operating mode is set by the card controller
when the Off-Hook condition has been recognized.
When this operating mode is selected the two output buffers (TIP/RING) can sink or source up to
100mA each. In case of Ground key or line terminals to GND the output current is limited to 15mA
for the Tip wire and 30mA for the Ring wire.
As far as the DC characteristic is concerned three
different feeding conditions are present:
a) Current limiting region: the DC impedance of
the SLIC is very high ( 20Kohm) and therefore the
system works like a current source. Using the
L3037 digital interface it is possible to select the
value of the limiting current:
25mA, 44mA, or 55mA.
When the device is in limiting current region the
negative supply for the output buffer is fixed by
5/22
L3037
the ext. transistor to a proper value higher than
the real negative battery in order to reduce the
power dissipated by the L3037 itself.
b) Resistive feed region: the characteristic is
equal to a battery voltage (Vbat) in series with a
resistor (typ 400ohm or 800ohm) whose value is
set by one ext. resistor (see ext. components list).
c) Constant voltage region: the characteristic is
equal to the battery voltage - 12V in series with
the ext. protection resistors (typ 80ohm).
This voltage drop between battery and line terminals for Il=0 allows on-hook transmission.
Fig. 1 shows the DC characteristic in active
mode. Fig. 2 shows the line current versus loop
resistance
Figure 1: DC Characteristic in active mode
Figure 2: Current vs. Loop Resistance.
Rfeed = 2 x 200ohm,
Lim. currents: 25, 43, 55mA
In active mode the AC impedance at the line terminals is sinthetized by the external components
ZAC and Rp according to the following formula:
Zs = ZAC/50 + 2*Rp
Depending on the characteristic of the ZAC network Zs can be either a pure resistance or a complex impedance. This allows L3037 to meet different standard as far as return loss is concerned.
The capacitor CCOMP guarantees stability to the
system.
The two to four wire conversion is achieved by
means of a circuit that can be represented as a
Wheastone bridge, the branches of which are:
6/22
1) The line impedance (Zline)
2) The SLIC impedance at line terminals (Zs)
3) The balancing network ZA+RA connected
between pin ZAC and ZB of L3037.
4) The network ZB between pin ZB and GND
that shall copy the line impedance.
When L3037 is used with a second generation
combo (eg TS5070FN) which is able to perform the
two to four wire conversion, the two impedances
ZA and ZB can be removed and the ZB pin connected to GND. The -6dB TX gain of the L3037 allows the echo signal to remain always within the
COMBOII Hybrid balance filter dynamic range.
The injection of high frequency metering pulses is
carried out through the SLIC. An unbalanced 12 or
16KHz sinusoidal signal with shaping is, when necessary, applied at the TTXIN input of the SLIC.
A fixed transfer gain is provided for the metering signal. To avoid saturation in the 4-wire side a cancellation is provided in the 4-wire transmission path.
Cancellation is obtained via an external RC network without the need for trimmed components.
When the TTX function is not used TTXIN input
should be connected to GND. Since this pin is directly connected to a summing node inside the
SLIC any signal applied to the TTXIN is transferred to the line with a fixed transfer gain.
In special applications, this pin can be used to
modify the voltage drop (constant voltage region
of DC characteristic) simply by applying a proper
DC level on the TTXIN pin, allowing optimization
of the battery voltage versus the maximum needed AC signal swing.
In active mode, with a -48V battery voltage, the
L3037 dissipate 150mW for its own operation (including the power dissipation from +5/-5 supply),
the dissipation related to the current supplied to
the line should be added in order to get the total
dissipation.
STAND-BY MODE (SBY)
In this mode the bias current of the L3037 is reduced and only some part of the circuit are completely
active. The transversal current supplied to the line
is limited at 14mA. Common mode current rejection
is performed and the total current capability of the
output stages (TIP and RING) is limited to 30mA.
The open circuit voltage is |Vbat|-7V.
Both Off/Hook and Ground key detectors are active. Signal transmission is not operating.
In stand-by mode, with a -48V battery voltage, the
L3037dissipates90mW typ. (including the power dissipationfrom a +5/-5V supply).
Stand-by mode is usually selected when the telephone is in on-hook condition. It allows a proper off-hook
detection, even in the presence of high common
mode currents, or with telephone sets sinking a few
milliamperes of line currentin on-hook condition.
L3037
CONTROL INTERFACE
INPUTS
D0
D1
GST
LIM
0
1
1
1
1
0
0
0
0
1
1
0
0
1
0
1
0
0
1
0
1
0
1
1
X
X
X
X (*)
X (*)
X
X
X
OPERATING MODE
POWER DOWN
STANDBY D. P.
STANDBY R. P.
ACTIVE D. P.
ACTIVE R. P.
RING
A. OPEN
RESERVED
OUTPUTS
ODET
OGK
DISABLE
OFF/HK
OFF/HK
OFF/HK
OFF/HK
RING-TRIP
OFF/HK
–
DISABLE
GDKEY
GDKEY
GDKEY
GDKEY
DISABLE
GDKEY
–
(*) LIM = 0 → Ilim = 25mA; LIM = H. I. (open) → Ilim = 44mA; LIM = 1 → Ilim = 55mA.
TIP OPEN MODE (TO)
This mode is selected when the SLIC is adopted
in a system using the Ground start feature. In this
mode the TIP termination is set in High Impedance (100Kohm) while the RING termination is active and fixed at Vbat + 4.5V. In the case of connection of RING termination to GND the sinked
current is limited to 30mA. When RING is connected to GND both off-hook and ground-key detectors become active.
Power dissipation in this mode with a -48V battery
voltage is 100mW (including the power dissipation from +5/-5V supply).
POWER DOWN MODE (PD)
In this mode, both TIP and RING terminations are
open and no current is fed into the line.
The power dissipation is very low.
This mode is usually selected in emergency condition or when the connected line is disabled.
This is also the mode into which the SLIC is automatically forced, in the case of thermal overload
T j > 150°C typ.
RINGING MODE (RNG)
When this mode is selected the ringing signal is
injected on the line via the ext relay activated by
the L3037 relay driver.
When the ringing signal phase is provided at the
RGIN pin, the relay command is also synchronized with the ringing signal zero crossing.
The TIP and RING termination of the L3037 are
senses the line current which is then integrated
on the CRT capacitor.
TIP pin voltage is fixed at – 2.5V, RING pin voltage is fixed at VBAT + 4.5V, TIP, RING buffer current capability is limited to 100mA.
When off-hook occurs during ringing burst the
voltage on CRT increase above a proper threshold and ring trip is detected.
Once ring trip is detected the ringing signal is
automatically disconnected at the first zero crossing. When the ringing signal phase is not provided at the RGIN pin the ringing signal is disconnected immediately after ring trip detection.
EXTERNAL COMPONENTS LIST
To set the SLIC into operation the following parameters have to be defined:
- The DC feeding resistance ”Rfeed” defined as
the resistance of
the traditional feeding
system (most common Rfeed values are:
400, 800, 1000 ohm).
- The AC SLIC impedance at line terminals ”Zs” to
which the return loss measurements is referred.
It can be real (typ. 600ohm) or complex.
- The equivalent AC impedance of the line ”Zl”
used for evaluation of the trans-hybrid loss
performance (2/4wire conversion). It is usually a complex impedance.
- The value of the two protection resistors Rp in
series with the line termination.
- The line impedance at the TTX freq. Zlttx.
- The reverse polarity transition time defined as
”∆VTR/∆T”.
Once, the above parameters are defined, it is
possible to calculate all the external components
using the following table.
The typical values has been obtained supposing:
- Rfeed = 400Ω
- Zs = 600Ω
- Zl = 600Ω
- Rp = 40Ω
- Zlttx = 216Ω + 120nF @ 12KHz
- Re[Zlttx] = 216Ω
- Im[Zlttx] = -110Ω @12KHz
- ∆VTR/∆T = 4250[V/s]
7/22
L3037
EXTERNAL COMPONENTS
Name
CVB
CVDD
CVSS
RREF
CSVR
CRT
RDC
CAC
RS
ZAC
ZA (1)
RA (1)
ZB (1)
CCOMP
CH (1)
Function
Battery Filter
Positive Supply Filter
Negative Supply Filter
Internal Current Reference
Battery Ripple Rejection
Ring Trip & Ground-key Capacitor
DC Feeding Resistance
AC/DC Splitter
Protection Resistor Image
2 Wire AC Impedance
SLIC Impedance Balancing Network
SLIC Impedance Balancing Network
Line Impedance Balancing Network
AC Feedback Compensation
RF
RT
RRG
Trans-hybrid Loss Frequency
Compensation
Feeding Resistance for Ring Inj.
Feeding Resistance for Ring Inj.
Ring Input Resistor
CRG
Ring Input Capacitor
PTC (2)
RST (2)
RSR (2)
QEXT
Rp
RTTX
CTTX
D1
CREV
Positive Temp. Coeff. Resistor
Tip Buffer Sensing Resistor
Ring Buffer Sensing Resistor
External Transistor (3)
Protection Resistor
Teletax Cancellation Resistor
Teletax Cancellation Capacitor
Relay Kickback Clamp Diode
Polarity Reversal Transition Time
Programming
Formula
Typ. Value
330nF 20% 63VI
100nF 20%
100nF 20%
23.7K 1%
680nF
20% 60VI
390nF 20% 6VI
3.2K 1%
4.7µF
20% 15VI
4K 1%
26K 1%
26K 1%
4K 1%
30K 1%
220pF
20%
220pF 20%
CSVR = 1/(6.28 * fp * 150K)
@ fp = 1.6Hz
CRT = (25/fRING) ⋅ 390nF
RDC = 10 * (Rfeed - 2Rp)
CAC = 1 / (6.28 * fsp * RDC)
@ fsp = 10Hz
RS = 50 * 2RP
ZAC = 50 * (Zs-2Rp)
ZA = 50 * (Zs-2Rp)
RA = 50 * 2Rp
ZB = 50 * Zl
CCOMP = 1 / [2Πfo (100 Rp)]
@ fo = 250KHz
CH = CCOMP
≥ 200Ω (7)
≥ 200Ω (7)
RRG = (VRING/25µA)cos[-2⋅fRING ⋅ T ⋅
180] (4)
CRG = 25µA/(VRING ⋅ sin[2 ⋅ fRING⋅T ⋅
180] ⋅ 2ΠfRING) (4)
< 15Ω
10 to 50KΩ
10 to 50KΩ
200Ω 2W
200Ω 2W
4MΩ 5%
3.9nF 20%
30 to 80Ω (8)
RTTX = 21.5 ⋅ [Re (Zlttx) +2Rp] (5)
CTTX = 1/(21.5 ⋅ [–Im(Zlttx) ⋅ fttx ⋅ 6.28])
(5)
CREV =
K
∆VTR ⁄ ∆T
100V
10Ω
33K 1W 5% (6)
33K 1W 5%(6)
(*)
40Ω
6.34K 1%
5.6nF 20%
; K = 2 ⋅ 10
-4
1N4148
47nF
Notes:
(1) These components can be removed and ZB pin shorted to GND when 2/4wire conversion is implemented with 2nd generation COMBO (EG.
TS5070FN)
(2) In case there is no necessity to recover the unbalance introduced by PTC tolerance pins TIP and STIP can be shorted togheter as pins
RING and SRING. In this case also the RP Resistor should be splitted in two parts keeping at least 20Ω between TIP/RING terminals and
protection connection. In this case PTC or fuse resistor (if used) can be placed in series to Rp.
(3) Transistor characteristic: PDISS = 1W (typ. depending on application); hFE ≥ 25; IC ≥ 100mA; V CEO ≥ 60V; fT ≥ 15MHz.
(4) VRING: Max Ring Generator Voltage, fRING: Ring Frequency, T: relay response time.
Typical value obtained for VRING = 100Vrms, fRING = 25Hz; T = 2.5ms.
(5) Defining RTTX + CTTX = ZTTX, RTTX and CTTX can also be calculated from the following formula: Z FTTX = 21.5 [Zlttx + 2Rp].
(6) RST and RSR wattage should be calculated according to the power cross test specification. (When PTC become open circuit the entire
power cross voltage will appear across RSR and RST).
(7) In order to optimize the component count it is also possible to use only one resistor in series to the ringing generator. In this case RT = 0Ω;
RF≥ 400Ω (RF typ. value = 400Ω).
(8) Suggested Rp type are 2W wire wound resistors or thick film resistors on ceramic substrate.
Fuse function should be included if PTC are not used.
(*) ex: BD140; MJE172;MJE350....(ST32 or SOT82 package available also for surface mount).
For low power application (reduced battery voltage) BCP53 (SOT223 surface mount package) can be used.
8/22
L3037
Figure 3: Typical Application Circuit including all features.
680nF
Figure 4: Typical Application circuit with minimum components count (No Rev. polarity NoTTX/No zero
crossing sync/no PTC mismatch compensation).
680nF
9/22
L3037
In case of U.S. application based on L3035 the
external components can be calculated supposing:
- Rfeed = 400Ω
- Zs = 900Ω + 2.12µF
- Zl = 1650Ω// (100Ω + 5nF) Loaded Line
- Zl = 800Ω// (100Ω + 50nF) Not Loaded Line
- Rp = 62Ω
EXTERNAL COMPONENTS (for US. Application)
Name
CVB
CVDD
CVSS
RREF
CSVR
CRT
RDC
CAC
RS
ZAC
ZA (1)
RA (1)
ZB (1)
CCOMP
CH (1)
RF
RT
RRG
CRG
PTC (2)
RST (2)
RSR (2)
QEXT
Rp
D1
Function
Battery Filter
Positive Supply Filter
Negative Supply Filter
Internal Current Reference
Battery Ripple Rejection
Ring Trip & Ground-key Capacitor
DC Feeding Resistance
AC/DC Splitter
Protection Resistor Image
2 Wire AC Impedance
SLIC Impedance Balancing Network
SLIC Impedance Balancing Network
Line Impedance Balancing Network
AC Feedback Compensation
Trans-hybrid Loss Freq. Comp.
Feeding Resistance for Ring Inj.
Feeding Resistance for Ring Inj.
Ring Input Resistor
Ring Input Capacitor
Positive Temp. Coeff. Resistor
Tip Buffer Sensing Resistor
Ring Buffer Sensing Resistor
External Transistor (5)
Protection Resistor
Relay Kickback Clamp Diode
Formula
CSVR = 1/(6.28 * fp * 150K)
@ fp = 1.6Hz
CRT = (25/fRING) ⋅ 390nF
RDC = 10 * (Rfeed - 2Rp)
CAC = 1 / (6.28 * fsp * RDC)
@ fsp = 10Hz
RS = 50 * 2RP
ZAC = 50 * (Zs-2Rp)
(7)
ZA = 50 * (Zs-2Rp)
(7)
RA = 50 * 2Rp
ZB = 50 * Zl
CCOMP = 1 / [2Πfo (100 Rp)]
@ fo = 250KHz
CH = CCOMP
≥ 200Ω (9)
≥ 200Ω (9)
RRG = (VRING/25µA)cos[-2⋅fRING ⋅ T ⋅
180] (6)
CRG = 25µA/(VRING ⋅ sin[2 ⋅ fRING⋅T ⋅
180] ⋅ 2ΠfRING (6)
< 15Ω
10 to 50KΩ
10 to 50KΩ
30 to 80Ω
Typ. Value
330nF 20% 63VI
100nF 20%
100nF 20%
23.7K 1%
680nF
20% 60VI
390nF 20% 6VI
2.76K 1%
4.7µF
20% 15VI
6.2K 1%
39K + (180K//55nF)
39K + (180K//55nF)
6.2K 1%
82.5K + (5K + 100pF) (3)
40K + (5K + 1nF) (4)
100pF
20%
100pF 20%
200Ω 2W
200Ω 2W
4MΩ 5%
3.9nF 20%
(10)
100V
10Ω
33K 1W 5%(8)
33K 1W 5%(8)
(*)
62Ω
1N4148
Notes:
(1) These components can be removed and ZB pin shorted to GND when 2/4wire conversion is implemented with 2nd generation COMBO (EG.
TS5070FN)
(2) In case there is no necessity to recover the unbalance introduced by PTC tolerance pins TIP and STIP can be shorted togheter as pins
RING and SRING. In this case also the RP Resistor should be splitted in two parts keeping at least 20Ω between TIP/RING terminals and
protection connection. In this case PTC or fuse resistor (if used) can be placed in series to Rp.
(3) Loaded Line.
(4) Not Loaded Line.
(5) Transistor characteristic: PDISS = 1W (typ. depending on application); hFE ≥ 25; IC ≥ 100mA; V CEO ≥ 60V; fT ≥ 15MHz.
(6) VRING: Max Ring Generator Voltage, f RING: Ring Frequency, T: relay response time. Typical value obtained for VRING = 100Vrms, f RING = 25Hz;
T = 2.5ms.
(7) For details see AN496.
(8) RST and RSR wattage should be calculated according to the power cross test specification. (When PTC become open circuit the entire
power cross voltage will appear across RSR and RST).
(9) In order to optimize the component count it is also possible to use only one resistor in series to the ringing generator. In this case RT = 0Ω;
RF≥ 400Ω (RF typ. value = 400Ω).
(10) Suggested Rp type are 2W wire wound resistors or thick film resistors on ceramic substrate.
Fuse function should be included if PTC are not used.
(*) ex: BD140; MJE172;MJE350....(SOT32 or SOT82 package available also for surface mount).
For low power application (reduced battery voltage) BCP53 (SOT223 surface mount package) can be used.
10/22
L3037
Figure 5: Typical Application Circuit for U.S. Application.
680nF
ELECTRICAL CHARACTERISTICS TEST CONDITION, unless otherwise specified: VCC = 5V;
VSS = -5V; VBAT = -48V; AGND = BGND; Direct Polarity; TA = 25°C.
Note: Testing of all parameters is performed at 25°C. Characterization as well as the design rules used
allow correlation of tested performances at other temperatures. All parameters listed here are
met in the range 0°C to +70°C. Functionality between -40°C and 85°C is verified.
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
INTERFACE REQUIREMENTS 2 WIRE PORT
V ab
Overload Level Voice Signal
Rp +PTC = 50Ω
300Hz to 3.4KHz (*)
Zll
Long Input Impedance
at SLIC terminals per wire
Ill
Long Current Capab. ac
Ill
Longitudinal Current Capability
4.1
Vpk
10
Ω
standby per wire (on HOOK)
17
mApk
active per wire (on HOOK)
17
mApk
active per wire off HOOK
(IT = Transversal current)
75-IT
mApk
4 WIRE TRANS PORT
Vtx
Overload Level
1.8
Vtoff
Output Offset Voltage
-350
Ztx
Output Impedance
Vpk
+350
mV
10
Ω
(*) At TIP/RING line connection with ZLINE (AC) = 600Ω. For any DC Loop current from 0mA to I LIM
11/22
L3037
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
4 WIRE RECEIVE PORT
ZRX
Input Impedance
100
KΩ
VRX
Overload Level
3.2
Vpk
100
KΩ
2
V
METERING INPUT PORT
ZMIN
Input Impedance
LOGIC CONTROL PORT
INPUT D0, D1, GST
Vih
Input High Voltage
Vil
Input Low Voltage
0.8
V
Iih
Input High Current
-10
90
µA
Iil
Input Low Current
-10
10
µA
C in
Input Capacitance
10
pF
0.4
V
INPUT LIM
Vih
Input High Voltage
Vil
Input Low Voltage
2.4
V
Iih
Input high Current
-10
30
µA
Iil
Input Low Current
-30
10
µA
C in
Input Capacitance
10
pF
0.4
V
OUTPUT DET
Vol
Output Low Voltage
Io = 2mA
V oh
Output High Voltage
Io = 30µA
Io ≤10µA
C ld
Load Capacitance
2.4
3.8
V
V
150
pF
-0.5
0.5
V
Input Impedance
50
90
KΩ
Offset Voltage Allowed
-15
15
mV
RINGING INPUT PORT
Overload Level
TRANSMISSION PERFORMANCE
Arl
Return Loss (2-wire)
300Hz to 3.4KHz
22
dB
Thl
Transhibrid Loss
300Hz to 3.4KHz
30
dB
52
dB
58
dB
49
dB
49
dB
20log10 
VRX

VTX
Longitudinal balance (CCITT Rec.0.121)
L-T
Longit to Transversal
L-4
Long Sign Rejection
T-L
Transvers to Longit
4-L
Long Sign Generation
300Hz to 3.4KHz
ZS = 600Ω
R P = 40Ω, 1% tolerance
Selected L3037 Longitudinal balance (IEEE Std 455-1976)
L–T
Longitudinal to Transversal
L –4
Longitudinal Signal Rejection
12/22
300Hz to 3.4KHz
ZS = 900Ω + 2.12µF
R P = 62Ω, 1% match
58
63
dB
70
dB
L3037
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
INSERTION LOSS
Gt
Transmit V Gain
Gr
Receive V Gain
0dBm, 1KHz
-6.22
-5.82
dB
-0.2
0.2
dB
-0.1
0.1
dB
-0.1
0.1
dB
VTTXIN = 0.66Vrms ZL =200Ω;
2 ⋅ RP = 80Ω; Vmoff = 0
3.18
3.51
-55dBm to 7dBm (1)
INSERTION LOSS vs. FREQUENCY (rel 1KHz / 0dBm)
Gt
Transmit V Gain
Gr
Receive V Gain
0.3 to 3.4KHz
METERING INJECTION
GTTX
Transfer Gain
THD
Harmonic Distortion
5
%
-0.1
0.1
dB
-0.1
0.1
dB
GAIN LINEARITY (rel 1KHz, -4dBm)
Gt
Transmit V Gain
Gr
Receive V Gain
GROUP DELAY (2-4, 4-2) 0DbM
TgABS
Absolute
3KHz
5
µs
TgDIS
4 to 2-wire
0.5 to 3,4KHz
5
µs
TOT HARMONIC DISTORTION
Thd4
2 to 4-wire
Thd2
4 to 2-wire
7dBm, 0.3 to 3.4KHz
-46
dB
-46
dB
IDLE CHANNEL NOISE
Vabp
2-wire port
psophometric
-78
-72
dBmP
Vtxp
4-wire transmit
psophometric
-82
-76
dBmP
Vabc
2-wire port
c message
12
18
dBr nC
Vtxc
4-wire transmit
c message
8
14
dBr nC
70
mV
RINGING FUNCTION
0 cross
IRT
TRTD
Zero Crossing Threshold Level
fRING = 16 to 66Hz
R GIN = 3Vrms
-70
Ring Trip Threshold
Ring Trip Detection Time
7.5
mA DC
R L = 1.8k, fRING = 25Hz
150
ms
mA
BATTERY FEED CHARACTERISTIC
POWER DOWN STATE
ILGND
Loop Current
TIP or RING to BGND
0.5
ILBAT
Loop Current
TIP or RING to Vbat
0.5
mA
IL
Loop Current
RL = 0
1
mA
STAND BY STATE
Il
VLOS
Iloop Accuracy
constant region
13
16
mA
Line Voltage
@ IL = 0
40
42
V
@ IL = 0
34.5
37.5
V
ACTIVE STATE
V LO
Line Voltage
R feed
Feeding Resistance Accuracy
Ilim
Loop Current Limit Accuracy
-10
Ilim = 25mA, 44mA, 55mA
-8
Ilim
+10
%
+8
%
GROUND START STATE
ZTIP
Tip Lead Impedance
IGS
Ring Lead Current
100
RING to GND
KΩ
30
mA
(1) For level lower than -40dB guaranteed by correlation.
13/22
L3037
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
DETECTORS
OFF HOOK DETECTOR
Idet
Off-hook Current Threshold
stand by state
9
12
mA
Idet
Off-hook Current Threshold
active state
9
12
mA
Hys
Off-hook / On-hook Hysteresys
Both stand by and active state
1
1.6
mA
Td
Dialling Distortion
active state
-1
1
ms
GROUND KEY DETECTOR
ILL
Ground Key Current Threshold
ILL = (IB - IA) / 2
TIP to RING to GND
or RING to GND
4
mA
POWER DISSIPATION ON L3037 at VBAT = 48V
Pd
Power Down
any line lenght
38
mW
Pd
Stand-by
2-wire open
R L = 0 to 2K
95
136
250
mW
mW
Pd
Active, Rfeed = 800Ω
ILIM = 25mA
ILIM = 44mA
ILIM = 55mA
2-wire open
R L = 0 to 2K
R L = 0 to 2K
R L = 0 to 2K
155
224
710
1730
2660
mW
mW
mW
mW
Pd
Active, Rfeed = 400Ω
ILIM = 25mA
ILIM = 44mA
ILIM = 55mA
2-wire open
R L = 0 to 2K
R L = 0 to 2K
R L = 0 to 2K
155
224
510
870
1280
mW
mW
mW
mW
Pd
Active
Ground Key
1500
mW
POWER DISSIPATION ON QEXT AT Vbat = 48V
P dq
P dq
Active, Rfeed = 800Ω
ILIM = 25mA
ILIM = 44mA
ILIM = 55mA
R L = 0 to 2K
R L = 0 to 2K
R L = 0 to 2K
880
810
420
mW
mW
mW
Active, Rfeed = 400Ω
ILIM = 25mA
ILIM = 44mA
ILIM = 55mA
R L = 0 to 2K
R L = 0 to 2K
R L = 0 to 2K
1080
1610
1670
mW
mW
mW
mA
SUPPLY CURRENTS
ANALOG SUPPLY
ICC
VCC
Power Down
1.5
2.2
ISS
VSS
Power Down
0.1
0.5
mA
ICC
VCC
Stand-by / A open
4
5
mA
ISS
VSS
Stand-by / A open
1.5
3
mA
ICC
VCC
Active
6
10
mA
ISS
VSS
Active
3
6
mA
BATTERY SUPPLY
14/22
Ibat
Power down
a or b to BGND
120
500
µA
Ibat
Stand-by
2-wire open
1.4
2
mA
Ibat
Active
2-wire open
2-wire RL = 400Ω
2.3
3
ILOOP+5
mA
mA
L3037
ELECTRICAL CHARACTERISTICS (continued)
Symbol
Parameter
Test Condition
Min.
Typ.
Max.
Unit
POWER SUPPLY REJECTION (VRIPPLE = 100mVrms)
LINE TERMINALS
PSRR
VCC ref to AGND
PSRR
PSRR
PSRR
50Hz to 3.4KHz
20
dB
VSS ref to AGND
20
dB
Vbat ref to AGND
30
dB
BGND ref to AGND
20
dB
RELAY DRIVER
iRD
Current Capability
V
Voltage Drop
iLK
Off Leakage Current
40
mA
@IRD = 40mA
1.25
V
100
µA
Figure 6: Test Circuit
680nF
15/22
L3037
680nF
Figure 7: Typical Application with 2nd Generation COMBO (600Ω Application)
16/22
L3037
680nF
Figure 8: Typical Application with 1st Generation COMBO (600Ω Application)
17/22
L3037
680nF
Figure 9: Typical Application with 2nd Generation COMBO (U.S. Application)
18/22
L3037
680nF
Figure 10: Typical application with 1st Generation COMBO (U.S. Application)
19/22
L3037
PLCC44 PACKAGE MECHANICAL DATA
mm
DIM.
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
17.4
17.65
0.685
0.695
B
16.51
16.65
0.650
0.656
C
3.65
3.7
0.144
0.146
D
4.2
4.57
0.165
0.180
d1
2.59
2.74
0.102
0.108
d2
E
0.68
14.99
0.027
16
0.590
0.630
e
1.27
0.050
e3
12.7
0.500
F
0.46
0.018
F1
0.71
0.028
G
20/22
inch
0.101
0.004
M
1.16
0.046
M1
1.14
0.045
L3037
PQFP44(10 x 10) PACKAGE MECHANICAL DATA
mm
DIM.
MIN.
inch
TYP.
MAX.
A
MIN.
TYP.
MAX.
2.45
A1
0.25
A2
1.95
B
0.096
0.010
2.00
2.10
0.077
0.079
0.30
0.45
0.012
0.018
c
0.13
0.23
0.005
0.009
D
12.95
13.20
13.45
0.51
0.52
0.53
D1
9.90
10.00
10.10
0.390
0.394
0.398
D3
8.00
0.315
e
0.80
0.031
0.083
E
12.95
13.20
13.45
0.510
0.520
0.530
E1
9.90
10.00
10.10
0.390
0.394
0.398
E3
8.00
L
0.65
0.315
0.80
L1
0.95
0.026
0.031
1.60
0.037
0.063
K
0°(min.), 7°(max.)
D
D1
A
A2
D3
A1
23
33
22
34
0.10mm
.004
44
B
E
E1
B
E3
Seating Plane
12
11
1
C
L
L1
e
K
PQFP44
21/22
L3037
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Mi croelectronics assumes no responsibility for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specification mentioned
in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. SGSTHOMSON Microelectronics products are not authorized for use as critical components in life support devices or systems without express
written approval of SGS-THOMSON Microelectronics.
 1997 SGS-THOMSON Microelectronics – Printed in Italy – All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
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22/22